Lock for drop-leaf swivel extension tables



Dec. 2, 1952 E. P. CHARAK LOCK FOR DROP-LEAF SWIVEL EXTENSION TABLES Filed Jan. 5, 1950 INVENTORL flsreg P Church Patented Dec. 2, 1952 UNITED STATES P TENT OFFICE LOCK FOR DROP-LEAF SWIVEL EXTENSION TABLES Application January 3, 1950, Serial N 0. 136,490

2 Claims. 1

The present invention relates to an improvement in drop leaf swivel type extension tables of the type disclosed in my prior patents, Nos. 1,969,875 and 2,092,244.

In the first patent mentioned, there is shown a drop leaf swivel type extension table in which the drop leaves are raised to a level table position and then the whole top is swiveled around a central axis at right angles to the initial drop leaf position, after which the table may be extended. In my patent, No. 2,092,244, I disclosed a means of locking the table when it has been turned to the position preparatory for extension. This means, however, is a manually operable means and while satisfactory in every respect, does not offer the great convenience ofiered in the present construction, in which the table top when moved into its rotated position, is secured in the manner that is necessary for full and convenient utility.

After careful and long observations, I have discovered that in tables of the present construction, namely those shown in my prior patents, it is necessary to exert only a very slight restraint against rotation of the top in the reversed direction of rotation, that is, from the extension type position to the drop leaf position in order to have the top sufficiently secured against rotation. I have further discovered that with the type of latching or holding arrangement used in the present invention, there is automatically imposed such a restraint, suificient to make it necessary to exert a positive turning force When it is desired to fold the table and that otherwise the table top cannot accidently be turned. The present invention does away with manually screwing the locking element in place and also avoids the use of spring tension latches which snap in place and may stick, or any type of springs for this purpose.

The invention will be more fully described in connection with the drawings illustrating the same as applied to a drop leaf swivel type extension table referred to in the above patents, wherem-- Figure 1 shows a fragmentary perspective view of a portion of the table illustrating the present invention.

Figure 2 shows a fragmentary view with parts in section looking against the upper end of the table as viewed in Figure 1.

Figure 3 shows a plan view of a detail shown in Figure 1, and Figure 4 shows a plan view on a smaller scale than the other figures of the table With the top removed.

In the arrangement indicated in the drawings, the table top I is supported by means of a socalled butterfly hinge 2 which pivots around a vertical pivot 3 so that the top I is turna-ble in a horizontal plane. The lower half of the butterfly hinge is attached to the bridge element 4 which is attached at both ends to the slide stringers 5 which slide longitudinally in the frame, a portion of which is indicated at 6. The slide stringers 5 are connected by the end finishing pieces 'I which are also securedto the side finishing pieces 8 and 9 (see Figure 4). These finishing pieces are the outside finishing frame members of the table just under the table top upon which the table top rests and are of finished Wood as the external portions of the table are eX- pected to be. As indicated more clearly in Figure 4, an arcuate series of slots [0 and II are made across the top edge of the finished element 8 and across one of the slide stringers 5 respectively. These arcuate slots have as a center the pivoting axis 3 and have both the same radius. Attached to the end finished end element 1 of the table is an angular bracket l2 which is attached to the inside face of the element 1 by means of screws or pegs l3. The bracket [2 is a right angle bracket with a horizontal section 14 positioned just below the top edge of the member I. This horizontal plate section of the bracket has formed therein a U-shaped slot l5 which opens in the direction of the slot H but is in fact substantially straight without a curvature and from the open end of the slot has the same radius distance to the pivot 3 as the arcuate slots II and ID. The table top has a bushing 16 threaded into it which permanently remains in position. This bushing has an internal thread [1 engaging the shank l8 of the screw [9 which is locked by a lock washer 20 permitting the head 2| of the screw to be set in the desired position from the under surface of the table.

As indicated in Figure 2, the screw head 2| is set and locked in position so that its inner shoulder 22 will be just below the lower surface of the plate I4 of the bracket l2. The shank of the screw I9 is of such a diameter as to engage the slot l5 for a good slide fit. Since the slot [5 is substantially horizontal when the screw shank enters the slot, there will be a slight tendency to engage or rub along the inner edge 23 of the slot. This may be emphasized sufficiently to make a close or tight fit as the table top is turned to an extension position prior to actual extension of the table. After engagement of the shank of the screw [9 with the edge 23' of the slot, the screw will easily slide to the inner end and remain substantially in a locked position.

It will be noted in the operation of the table that after the drop leaves are raised, the top is then turned while the two inner leaves are in substantially contacting position. It is in this operation that the screw is made to engage the locking slot. Thereafter, the table may be opened for the insertion of the leaves since the finished pieces 7, 8, and 9 around the bottom of the table top extend with the extension of the top. The top is, therefore, always locked in position. The head 2| of the locking screw is of course of greater diameter than the width of the slot [5, so that the top cannot be raised.

The construction in the present invention provides a very firm top, first, inasmuch as the top is actually locked down to the frame, and secondly, the engagement of the slot in the bracket offers friction to a transverse motion on any side of the table except when the table top is grasped at both ends and a slight outward pull is given which exerts sufficient strain so that the top may then be turned clear as for instance when closing the table.

Having now described my invention, I claim:

1. In combination with a drop leaf swivel type extension table having unconnected abutting center leaves each with an adjoining drop leaf forming the table top in its unextended position with the abutting leaves pivoted in an axis perpendicularly to the table top plane at the center of the table with the pivoting means attached to the extensible frame of the table, said extensible frame having a transverse supporting element, an angle bracket attached thereto having a plate member parallel with the table top with a U- shaped slot extending inward from one side, one of said leaves having on its underside a stud element with a cap thereon projecting below the surface of the leaf, the inner surface of the cap element being slightly lower than the lower face of the plate at the engaging end of the U-shaped slot and said slot being at the same radius from said pivot as said stud and extending substantially in the same direction of rotation.

2. In combination with a table as set forth in claim 1 in which said stud element comprises a cap headed screw, a threaded bushing set in said table for receiving said screw and a lock washer for locking the screw in the desired position whereby the inner surface of the cap will abut the lower side of the plate of the angle member.

ES'I'EY P. CHARAK.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,212,897 Brown Jan. 16, 1917 2,075,881 Bekius Apr. 6, 1937 2,092,244 Charak Sept. 7, 1937 2,187,423 Hyland Jan. 16, 1940 

